[Morphologic and functional aspects of left ventricular hypertrophy evaluated by computerized echocardiography].

Abstract

We have investigated the possible echocardiographic progression of left ventricular (LV) hypertrophy, in different stages of primary hypertension. Both morphological (LV mass and ratio of interventricular septal thickness to posterior wall thickness-IVST/PWT-, in M-mode) and functional data (parietal stress, duration, degree and velocity of filling in the four phases of diastole, obtained through computerised interpretation of M-mode tracings), were examined. We also tried to assess the morphofunctional differences between LV hypertrophy secondary to primary hypertension and LV hypertrophy secondary to renovascular hypertension, hypertrophic obstructive cardiomyopathy and physical training. Patients with primary hypertension were further subdivided in three groups: A) 14 patients with hypertension of less than one year's duration, B) 28 patients with long-lasting hypertension, and C) 5 patients with cardiomegaly. There was a progressive increase from controls to Group C patients of left ventricular mass (controls 171 +/- 25; Group A 168 +/- 72; Group B 253 +/- 83; Group C 439 +/- 117) and septal hypertrophy (controls IVST/PVT 1 +/- 0.1; Group A 1.2 +/- 0.2; Group B 1.4 +/- 0.3; Group C 1.5 +/- 0.1). The isovolumic relaxation period was prolonged only in Group C (controls 8.6 +/- 3.5 per cent of the diastole; Group C 15 +/- 3.5%) LV dimensions during slow filling and atrial contraction as well as filling velocity during this latter phase of the cardiac cycle were increased in Group A (7.8 +/- 2.3 and 7.3 +/- 2%; 1.2 +/- 0.6 cm/cm X sec respectively) and B (10 +/- 6 and 10.8 +/- 4%; 1.2 +/- 0.6 cm/cm X sec) compared to the controls (5 +/- 2.8 and 3.7 +/- 2%; 0.7 +/- 0.2 cm/cm X sec). The Vcf max was not significantly different in the three groups. The patients with renovascular hypertension (N = 14) could be differentiated from those with primary hypertension of Group B for a greater increase in LV mass, with concentric hypertrophy (IVST/PWT = 1.2 +/- 0.2), for a greater prolongation of IRP (16 +/- 0.6% of diastole), with increased diameter changes in this phase (displacement ratio = 3.3 +/- 2.3%, in Group B; 4.7 +/- 3.8%, in renovascular hypertension), for a normal displacement and velocity of slow and atrial filling, despite the impairment of rapid filling found in this group, too (% displacement and velocity, respectively: 19 +/- 5% and 1.8 +/- 0.6 cm/cm X sec).